...as I am using a GF3 now and planning to buy the GM1, is it as big an IQ upgrade as some would lead to believe. I'm sure its pretty substantial, but after using a GF3 would you give it a definitve yes?

As for the chart, well, Sony does a real good job on their 1 inchers and the RX100/II are basically the cream of the compact crop so good for them. I would expect such findings.